216 Kendall : Notes on Geology. 



Ferribv Common, near Hull. 



Chalky gravel in a small pit on the Humber side contains a 

 small percentage of foreign rocks, including" rhomb-porphyry, 

 basalt, carboniferous limestone. 



Thornton Dale, Yale of Pickering. 



In the cutting- east of the station, through beds mapped as 

 glacial, no trace of foreign rocks seen, all local oolite. 



Reported by F. F. Walton, F.G.S. 



Hornsea. 



One volcanic breccia, 4 in. x 3 in. x 3 in., identical with 

 boulders found in stream at Dunmail Raise, Cumberland. 

 One quartz porphyry (Armboth Dyke), 4 in. x 3 in. x 3 in. 



NOTES on YORKSHIRE GEOLOGY. 



Current Bedding in the Carboniferous Limestone.— Mr. R. H. 



Tiddeman, in his suggestive papers on the limestone knolls of Craven, 

 has expressed the opinion that the Carboniferous Limestone on the upthrow 

 (northern) side of the southern Craven fault was accumulated in shallow 

 water. On a visit to Malham about three years ago I found several angular 

 fragments of distinctly current-bedded limestone in the screes above the 

 waterfall at Gordale Scar. I have made no attempt to trace these blocks 

 to the bed from which they originate, and I think it would be a profitable 

 task for some of our young and active geologists. — P. F. Kendall, Leeds, 

 7th June 1902. 



Origin of the Rosedale Ironstone. — Mr. C. Fox Strangways 

 mentions in his great Monograph of the Jurassic Rocks of Yorkshire the 

 occurrence of ' water-worn fragments of Belemnites and Ammonites, the 

 latter being unmistakable Lower Lias forms,' in the Dogger at Saltwick, 

 near Whitby. In other parts of his memoir he describes the evidences of 

 erosion of the Upper Lias prior to the deposition of the Dogger. A small 

 observation I made two or three years ago throws some additional light 

 upon the matter. My friend Rev. J. Hawell, F. G.S., showed me the 

 spoil of an old excavation in the Middle Lias near Kildale Station, and 

 I at once recognised in the ferruginous oolitic ironstone a very strong 

 resemblance to the ironstone pebbles which we had seen a few days 

 previously in the Dogger at the Wain Stones, near Ingleby Greenhow. Two 

 ideas present themselves to my mind regarding these facts — one, that as 

 there was an extensive denudation of the Lias during the deposition of the 

 Dogger, it is not improbable that the Dogger ironstone mav have derived 

 much of its material from the denudation of the Middle Lias ironstone. 

 The other reflection is that, as the lowest horizon of the Lias to which the 

 Dogger erosion-plane has cut in the Cleveland area is still above the 

 Jet-rock, there must exist elsewhere some old axis of disturbance along* 

 which the Lias was folded and denuded before or during the Dogger time 

 actually down to the Lower Lias. As the Upper Lias is practically intact 

 right down to the Humber, except for Pre-cretaceous erosion on the 

 Market Weighton anticline, I think that the source of the Lower and 

 Middle Lias debris in the Dogg-er must be sought to the north of the 

 Cleveland area, perhaps on some of the folds which can be shown to have 

 been produced in pre-Permian times and accentuated by subsequent move- 

 ment. — P. F. Kendall, Leeds, 7th June 1902. 



Naturalist, 



